| Message ID | 8cd5e1b763951d4ce69188cdff95d8adaf12755f.1673227292.git.zhoubinbin@loongson.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | rtc: ls2x: Add support for the Loongson-2K/LS7A RTC | expand |
在2023年1月9日一月 上午1:35，Binbin Zhou写道： > This RTC module is integrated into the Loongson-2K SoC and the LS7A > bridge chip. This version is almost entirely rewritten to make use of > current kernel API, and it supports both ACPI and DT. > > This driver is shared by MIPS-based Loongson-3A4000 system (use FDT) and > LoongArch-based Loongson-3A5000 system (use ACPI). > > Signed-off-by: Huacai Chen <chenhuacai@kernel.org> > Signed-off-by: WANG Xuerui <git@xen0n.name> > Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> # MIPS Loongson64 + DT > --- > drivers/rtc/Kconfig | 11 ++ > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-ls2x.c | 379 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 391 insertions(+) > create mode 100644 drivers/rtc/rtc-ls2x.c > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index bb63edb507da..f8586aa00fce 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -1735,6 +1735,17 @@ config RTC_DRV_LPC32XX > This driver can also be built as a module. If so, the module > will be called rtc-lpc32xx. > > +config RTC_DRV_LS2X > + tristate "Loongson LS2X RTC" > + depends on MACH_LOONGSON64 || COMPILE_TEST > + select REGMAP_MMIO > + help > + If you say yes here you get support for the RTC on the Loongson-2K > + SoC and LS7A bridge, which first appeared on the Loongson-2H. > + > + This driver can also be built as a module. If so, the module > + will be called rtc-ls2x. > + > config RTC_DRV_PM8XXX > tristate "Qualcomm PMIC8XXX RTC" > depends on MFD_PM8XXX || MFD_SPMI_PMIC || COMPILE_TEST > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index aab22bc63432..d5a467e9eec8 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -83,6 +83,7 @@ obj-$(CONFIG_RTC_DRV_LOONGSON1) += rtc-ls1x.o > obj-$(CONFIG_RTC_DRV_LP8788) += rtc-lp8788.o > obj-$(CONFIG_RTC_DRV_LPC24XX) += rtc-lpc24xx.o > obj-$(CONFIG_RTC_DRV_LPC32XX) += rtc-lpc32xx.o > +obj-$(CONFIG_RTC_DRV_LS2X) += rtc-ls2x.o > obj-$(CONFIG_RTC_DRV_M41T80) += rtc-m41t80.o > obj-$(CONFIG_RTC_DRV_M41T93) += rtc-m41t93.o > obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o > diff --git a/drivers/rtc/rtc-ls2x.c b/drivers/rtc/rtc-ls2x.c > new file mode 100644 > index 000000000000..06ef249a9485 > --- /dev/null > +++ b/drivers/rtc/rtc-ls2x.c > @@ -0,0 +1,379 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Loongson-2K/LS7A RTC driver > + * > + * Based on the original out-of-tree Loongson-2H RTC driver for Linux 2.6.32, > + * by Shaozong Liu <liushaozong@loongson.cn>. > + * > + * Maintained out-of-tree by Huacai Chen <chenhuacai@kernel.org>. > + * Rewritten for mainline by WANG Xuerui <git@xen0n.name>. > + * Binbin Zhou <zhoubinbin@loongson.cn> > + */ > + > +#include <linux/bitfield.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > +#include <linux/rtc.h> > +#include <linux/acpi.h> > + > +/* Time Of Year(TOY) counters registers */ > +#define TOY_TRIM_REG 0x20 /* Must be initialized to 0 */ > +#define TOY_WRITE0_REG 0x24 /* TOY low 32-bit value (write-only) */ > +#define TOY_WRITE1_REG 0x28 /* TOY high 32-bit value (write-only) */ > +#define TOY_READ0_REG 0x2c /* TOY low 32-bit value (read-only) */ > +#define TOY_READ1_REG 0x30 /* TOY high 32-bit value (read-only) */ > +#define TOY_MATCH0_REG 0x34 /* TOY timing interrupt 0 */ > +#define TOY_MATCH1_REG 0x38 /* TOY timing interrupt 1 */ > +#define TOY_MATCH2_REG 0x3c /* TOY timing interrupt 2 */ > + > +/* RTC counters registers */ > +#define RTC_CTRL_REG 0x40 /* TOY and RTC control register */ > +#define RTC_TRIM_REG 0x60 /* Must be initialized to 0 */ > +#define RTC_WRITE0_REG 0x64 /* RTC counters value (write-only) */ > +#define RTC_READ0_REG 0x68 /* RTC counters value (read-only) */ > +#define RTC_MATCH0_REG 0x6c /* RTC timing interrupt 0 */ > +#define RTC_MATCH1_REG 0x70 /* RTC timing interrupt 1 */ > +#define RTC_MATCH2_REG 0x74 /* RTC timing interrupt 2 */ > + > +/* TOY_WRITE0_REG bitmask */ > +#define TOY_MON GENMASK(31, 26) > +#define TOY_DAY GENMASK(25, 21) > +#define TOY_HOUR GENMASK(20, 16) > +#define TOY_MIN GENMASK(15, 10) > +#define TOY_SEC GENMASK(9, 4) > +#define TOY_MSEC GENMASK(3, 0) > + > +/* TOY_MATCH0/1/2_REG bitmask */ > +#define TOY_MATCH_YEAR GENMASK(31, 26) > +#define TOY_MATCH_MON GENMASK(25, 22) > +#define TOY_MATCH_DAY GENMASK(21, 17) > +#define TOY_MATCH_HOUR GENMASK(16, 12) > +#define TOY_MATCH_MIN GENMASK(11, 6) > +#define TOY_MATCH_SEC GENMASK(5, 0) > + > +/* RTC_CTRL_REG bitmask */ > +#define RTC_ENABLE BIT(13) /* 1: RTC counters enable */ > +#define TOY_ENABLE BIT(11) /* 1: TOY counters enable */ > +#define OSC_ENABLE BIT(8) /* 1: 32.768k crystal enable */ > + > +/* Offset of PM domain from RTC domain */ > +#define PM_RTC_OFFSET 0x100 > + > +/* PM domain registers */ > +#define PM1_STS_REG 0x0c /* Power management 1 status register */ > +#define RTC_STS BIT(10) /* RTC status */ > +#define PM1_EN_REG 0x10 /* Power management 1 enable register */ > +#define RTC_EN BIT(10) /* RTC event enable */ > + > +struct ls2x_rtc_priv { > + spinlock_t rtc_reglock; > + int irq; > + struct rtc_device *rtcdev; > + struct regmap *regmap; > + void __iomem *acpi_base; > +}; > + > +static const struct regmap_config ls2x_rtc_regmap_config = { > + .reg_bits = 32, > + .val_bits = 32, > + .reg_stride = 4, > +}; > + > +struct ls2x_rtc_regs { > + u32 reg0; > + u32 reg1; > +}; > + > +/* IRQ Handlers */ > +static irqreturn_t ls2x_rtc_isr(int irq, void *id) > +{ > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > + > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); > + return IRQ_HANDLED; > +} > + > +#ifdef CONFIG_ACPI > +static u32 ls2x_acpi_fix_handler(void *id) > +{ > + int ret; > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > + > + spin_lock(&priv->rtc_reglock); > + > + /* Disable acpi rtc enabled */ > + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; > + writel(ret, priv->acpi_base + PM1_EN_REG); > + > + /* Clear acpi rtc interrupt Status */ > + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); > + > + spin_unlock(&priv->rtc_reglock); > + > + /* > + * The TOY_MATCH0_REG should be cleared 0 here, > + * otherwise the interrupt cannot be cleared. > + * Because the match condition is still satisfied > + */ > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); > + if (ret < 0) > + return ret; > + > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); > + return 0; > +} > +#endif > + > +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, > + struct rtc_time *tm) > +{ > + tm->tm_year = regs->reg1; > + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); > + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); > + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); > + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); > + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; > +} > + > +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, > + struct ls2x_rtc_regs *regs) > +{ > + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); > + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); > + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); > + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); > + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); > + regs->reg1 = tm->tm_year; > +} > + > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > + struct rtc_time *tm) > +{ > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > + /* > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > + * years at most. Therefore, The RTC alarm years can be set from 1900 > + * to 1963. This causes the initialization of alarm fail during call > + * __rtc_read_alarm. > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > + * offset, the RTC alarm clock can be set from 1964 to 2027. > + */ > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; > +} > + > +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, > + struct ls2x_rtc_regs *regs) > +{ > + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); > +} > + > +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); > + if (ret < 0) > + return ret; > + > + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); > + if (ret < 0) > + return ret; > + > + ls2x_rtc_regs_to_time(®s, tm); > + return 0; > +} > + > +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ls2x_rtc_time_to_regs(tm, ®s); > + > + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); > + if (ret < 0) > + return ret; > + > + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); > +} > + > +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); > + if (ret < 0) > + return ret; > + > + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); > + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); > + > + return 0; > +} > + > +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > +{ > + u32 val; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + spin_lock(&priv->rtc_reglock); > + val = readl(priv->acpi_base + PM1_EN_REG); > + > + /* Enalbe RTC alarm */ > + writel((enabled ? val | RTC_EN : val & ~RTC_EN), > + priv->acpi_base + PM1_EN_REG); > + spin_unlock(&priv->rtc_reglock); > + > + return 0; > +} > + > +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); > + > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); > + if (ret < 0) > + return ret; > + > + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); > +} > + > +static const struct rtc_class_ops ls2x_rtc_ops = { > + .read_time = ls2x_rtc_read_time, > + .set_time = ls2x_rtc_set_time, > + .read_alarm = ls2x_rtc_read_alarm, > + .set_alarm = ls2x_rtc_set_alarm, > + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, > +}; > + > +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) > +{ > + u32 val; > + int ret; > + > + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); > + if (ret < 0) > + return ret; > + > + return regmap_write(priv->regmap, RTC_CTRL_REG, > + val | TOY_ENABLE | OSC_ENABLE); > +} > + > +static int ls2x_rtc_probe(struct platform_device *pdev) > +{ > + int ret; > + void __iomem *regs; > + struct ls2x_rtc_priv *priv; > + struct device *dev = &pdev->dev; > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->irq = platform_get_irq(pdev, 0); > + if (priv->irq < 0) > + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); > + > + platform_set_drvdata(pdev, priv); > + > + regs = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(regs)) > + return dev_err_probe(dev, PTR_ERR(regs), > + "devm_platform_ioremap_resource failed\n"); > + > + priv->regmap = devm_regmap_init_mmio(dev, regs, > + &ls2x_rtc_regmap_config); > + if (IS_ERR(priv->regmap)) > + return dev_err_probe(dev, PTR_ERR(priv->regmap), > + "devm_regmap_init_mmio failed\n"); > + > + priv->rtcdev = devm_rtc_allocate_device(dev); > + if (IS_ERR(priv->rtcdev)) > + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), > + "devm_rtc_allocate_device failed\n"); > + > + /* Due to hardware erratum, all years multiple of 4 are considered > + * leap year, so only years 2000 through 2099 are usable. > + * > + * Previous out-of-tree versions of this driver wrote tm_year directly > + * into the year register, so epoch 2000 must be used to preserve > + * semantics on shipped systems. > + */ > + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; > + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; > + priv->rtcdev->ops = &ls2x_rtc_ops; > + priv->acpi_base = regs - PM_RTC_OFFSET; > + spin_lock_init(&priv->rtc_reglock); > + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); > + > +#ifdef CONFIG_ACPI > + if (!acpi_disabled) > + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, > + ls2x_acpi_fix_handler, priv); > +#endif > + > + ret = ls2x_enable_rtc(priv); > + if (ret < 0) > + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); > + > + ret = devm_request_threaded_irq(dev, priv->irq, NULL, ls2x_rtc_isr, > + IRQF_TRIGGER_RISING | IRQF_ONESHOT, > + "ls2x-alarm", priv); > + if (ret < 0) > + return dev_err_probe(dev, ret, "Unable to request irq %d\n", > + priv->irq); > + > + if (!device_can_wakeup(&pdev->dev)) > + device_init_wakeup(dev, 1); > + > + return devm_rtc_register_device(priv->rtcdev); > +} > + > +static const struct of_device_id ls2x_rtc_of_match[] = { > + { .compatible = "loongson,ls2x-rtc" }, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match); > + > +static const struct acpi_device_id ls2x_rtc_acpi_match[] = { > + { "LOON0001" }, /* Loongson LS7A */ > + { } > +}; > +MODULE_DEVICE_TABLE(acpi, ls2x_rtc_acpi_match); > + > +static struct platform_driver ls2x_rtc_driver = { > + .probe = ls2x_rtc_probe, > + .driver = { > + .name = "ls2x-rtc", > + .of_match_table = ls2x_rtc_of_match, > + .acpi_match_table = ls2x_rtc_acpi_match, > + }, > +}; > + > +module_platform_driver(ls2x_rtc_driver); > + > +MODULE_DESCRIPTION("Loongson LS2X RTC driver"); > +MODULE_AUTHOR("WANG Xuerui <git@xen0n.name>"); > +MODULE_AUTHOR("Huacai Chen <chenhuacai@kernel.org>"); > +MODULE_AUTHOR("Binbin Zhou <zhoubinbin@loongson.cn>"); > +MODULE_LICENSE("GPL"); > -- > 2.31.1
Hello, On 09/01/2023 09:35:12+0800, Binbin Zhou wrote: > This RTC module is integrated into the Loongson-2K SoC and the LS7A > bridge chip. This version is almost entirely rewritten to make use of > current kernel API, and it supports both ACPI and DT. > > This driver is shared by MIPS-based Loongson-3A4000 system (use FDT) and > LoongArch-based Loongson-3A5000 system (use ACPI). > checkpatch.pl --strict complains, please fix the warnings and checks > +#ifdef CONFIG_ACPI > +static u32 ls2x_acpi_fix_handler(void *id) > +{ > + int ret; > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > + > + spin_lock(&priv->rtc_reglock); > + > + /* Disable acpi rtc enabled */ > + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; > + writel(ret, priv->acpi_base + PM1_EN_REG); > + > + /* Clear acpi rtc interrupt Status */ > + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); > + > + spin_unlock(&priv->rtc_reglock); > + > + /* > + * The TOY_MATCH0_REG should be cleared 0 here, > + * otherwise the interrupt cannot be cleared. > + * Because the match condition is still satisfied > + */ > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); > + if (ret < 0) > + return ret; How is this an ACPI related issue? I guess the same would happen on !ACPI. > + > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); This is not useful, at that time, userspace has had no chance to open the RTC device file as it is not created yet. > + return 0; > +} > +#endif > + > +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, Those static inline functions seem to be used only once, you should just put the code in the proper location. > + struct rtc_time *tm) > +{ > + tm->tm_year = regs->reg1; > + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); > + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); > + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); > + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); > + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; > +} > + > +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, > + struct ls2x_rtc_regs *regs) > +{ > + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); > + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); > + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); > + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); > + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); > + regs->reg1 = tm->tm_year; > +} > + > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > + struct rtc_time *tm) > +{ > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > + /* > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > + * years at most. Therefore, The RTC alarm years can be set from 1900 > + * to 1963. This causes the initialization of alarm fail during call > + * __rtc_read_alarm. > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > + * offset, the RTC alarm clock can be set from 1964 to 2027. > + */ > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; This is not symmetric with ls2x_rtc_time_to_alarm_regs, how can it work? > +} > + > +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, > + struct ls2x_rtc_regs *regs) > +{ > + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); > + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); > +} > + > +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); > + if (ret < 0) > + return ret; > + > + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); > + if (ret < 0) > + return ret; > + I never got a reply to my question: " I'm actually wondering why you read first TOY_READ1_REG then TOY_READ0_REG. ls1x does the opposite and the ls1c datasheet I found doesn't mention any latching happening. So unless latching is done on TOY_READ1_REG, you could use regmap_bulk_read and simply avoid struct ls2x_rtc_regs. If there is no latching, you may need to read TOY_READ0_REG at least twice. Because TOY_READ1_REG only contains the year, it is an issue only on 31 of December and it will not be easy to reproduce. " > + ls2x_rtc_regs_to_time(®s, tm); > + return 0; > +} > + > +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ls2x_rtc_time_to_regs(tm, ®s); > + > + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); > + if (ret < 0) > + return ret; > + > + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); > +} > + > +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); > + if (ret < 0) > + return ret; > + > + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); > + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); > + > + return 0; > +} > + > +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > +{ > + u32 val; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + spin_lock(&priv->rtc_reglock); > + val = readl(priv->acpi_base + PM1_EN_REG); > + > + /* Enalbe RTC alarm */ Typo > + writel((enabled ? val | RTC_EN : val & ~RTC_EN), > + priv->acpi_base + PM1_EN_REG); > + spin_unlock(&priv->rtc_reglock); > + > + return 0; > +} > + > +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > +{ > + int ret; > + struct ls2x_rtc_regs regs; > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > + > + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); > + > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); > + if (ret < 0) > + return ret; > + > + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); > +} > + > +static const struct rtc_class_ops ls2x_rtc_ops = { > + .read_time = ls2x_rtc_read_time, > + .set_time = ls2x_rtc_set_time, > + .read_alarm = ls2x_rtc_read_alarm, > + .set_alarm = ls2x_rtc_set_alarm, > + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, > +}; > + > +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) > +{ > + u32 val; > + int ret; > + > + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); > + if (ret < 0) > + return ret; > + > + return regmap_write(priv->regmap, RTC_CTRL_REG, > + val | TOY_ENABLE | OSC_ENABLE); > +} > + > +static int ls2x_rtc_probe(struct platform_device *pdev) > +{ > + int ret; > + void __iomem *regs; > + struct ls2x_rtc_priv *priv; > + struct device *dev = &pdev->dev; > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->irq = platform_get_irq(pdev, 0); > + if (priv->irq < 0) > + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); > + > + platform_set_drvdata(pdev, priv); > + > + regs = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(regs)) > + return dev_err_probe(dev, PTR_ERR(regs), > + "devm_platform_ioremap_resource failed\n"); > + > + priv->regmap = devm_regmap_init_mmio(dev, regs, > + &ls2x_rtc_regmap_config); > + if (IS_ERR(priv->regmap)) > + return dev_err_probe(dev, PTR_ERR(priv->regmap), > + "devm_regmap_init_mmio failed\n"); > + > + priv->rtcdev = devm_rtc_allocate_device(dev); > + if (IS_ERR(priv->rtcdev)) > + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), > + "devm_rtc_allocate_device failed\n"); > + > + /* Due to hardware erratum, all years multiple of 4 are considered > + * leap year, so only years 2000 through 2099 are usable. > + * > + * Previous out-of-tree versions of this driver wrote tm_year directly > + * into the year register, so epoch 2000 must be used to preserve > + * semantics on shipped systems. > + */ > + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; > + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; > + priv->rtcdev->ops = &ls2x_rtc_ops; > + priv->acpi_base = regs - PM_RTC_OFFSET; > + spin_lock_init(&priv->rtc_reglock); > + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); Why? > + > +#ifdef CONFIG_ACPI > + if (!acpi_disabled) > + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, > + ls2x_acpi_fix_handler, priv); > +#endif > + > + ret = ls2x_enable_rtc(priv); > + if (ret < 0) > + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); This should not be done in probe but on the first set_time. This then allows you to know whether the time has been set and is valid in read_time. Please add the check. > + > + ret = devm_request_threaded_irq(dev, priv->irq, NULL, ls2x_rtc_isr, > + IRQF_TRIGGER_RISING | IRQF_ONESHOT, > + "ls2x-alarm", priv); > + if (ret < 0) > + return dev_err_probe(dev, ret, "Unable to request irq %d\n", > + priv->irq); > + > + if (!device_can_wakeup(&pdev->dev)) > + device_init_wakeup(dev, 1); > + > + return devm_rtc_register_device(priv->rtcdev); > +} > + > +static const struct of_device_id ls2x_rtc_of_match[] = { > + { .compatible = "loongson,ls2x-rtc" }, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match); > + > +static const struct acpi_device_id ls2x_rtc_acpi_match[] = { > + { "LOON0001" }, /* Loongson LS7A */ > + { } > +}; > +MODULE_DEVICE_TABLE(acpi, ls2x_rtc_acpi_match); > + > +static struct platform_driver ls2x_rtc_driver = { > + .probe = ls2x_rtc_probe, > + .driver = { > + .name = "ls2x-rtc", > + .of_match_table = ls2x_rtc_of_match, > + .acpi_match_table = ls2x_rtc_acpi_match, > + }, > +}; > + > +module_platform_driver(ls2x_rtc_driver); > + > +MODULE_DESCRIPTION("Loongson LS2X RTC driver"); > +MODULE_AUTHOR("WANG Xuerui <git@xen0n.name>"); > +MODULE_AUTHOR("Huacai Chen <chenhuacai@kernel.org>"); > +MODULE_AUTHOR("Binbin Zhou <zhoubinbin@loongson.cn>"); > +MODULE_LICENSE("GPL"); > -- > 2.31.1 >
Hi Alexandre: Sorry for the late reply. On Tue, Jan 24, 2023 at 7:37 AM Alexandre Belloni <alexandre.belloni@bootlin.com> wrote: > > Hello, > > > On 09/01/2023 09:35:12+0800, Binbin Zhou wrote: > > This RTC module is integrated into the Loongson-2K SoC and the LS7A > > bridge chip. This version is almost entirely rewritten to make use of > > current kernel API, and it supports both ACPI and DT. > > > > This driver is shared by MIPS-based Loongson-3A4000 system (use FDT) and > > LoongArch-based Loongson-3A5000 system (use ACPI). > > > > checkpatch.pl --strict complains, please fix the warnings and checks Got. > > > > +#ifdef CONFIG_ACPI > > +static u32 ls2x_acpi_fix_handler(void *id) > > +{ > > + int ret; > > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > > + > > + spin_lock(&priv->rtc_reglock); > > + > > + /* Disable acpi rtc enabled */ > > + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; > > + writel(ret, priv->acpi_base + PM1_EN_REG); > > + > > + /* Clear acpi rtc interrupt Status */ > > + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); > > + > > + spin_unlock(&priv->rtc_reglock); > > + > > + /* > > + * The TOY_MATCH0_REG should be cleared 0 here, > > + * otherwise the interrupt cannot be cleared. > > + * Because the match condition is still satisfied > > + */ > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); > > + if (ret < 0) > > + return ret; > > How is this an ACPI related issue? I guess the same would happen on > !ACPI. I just assumed that the function would only be called under CONFIG_ACPI. > > > + > > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); > > This is not useful, at that time, userspace has had no chance to open > the RTC device file as it is not created yet. > > > + return 0; > > +} > > +#endif > > + > > +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, > > Those static inline functions seem to be used only once, you should just > put the code in the proper location. I will do it in the next version. > > > + struct rtc_time *tm) > > +{ > > + tm->tm_year = regs->reg1; > > + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); > > + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); > > + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); > > + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); > > + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; > > +} > > + > > +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, > > + struct ls2x_rtc_regs *regs) > > +{ > > + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); > > + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); > > + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); > > + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); > > + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); > > + regs->reg1 = tm->tm_year; > > +} > > + > > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > > + struct rtc_time *tm) > > +{ > > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > > + /* > > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > > + * years at most. Therefore, The RTC alarm years can be set from 1900 > > + * to 1963. This causes the initialization of alarm fail during call > > + * __rtc_read_alarm. > > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > > + * offset, the RTC alarm clock can be set from 1964 to 2027. > > + */ > > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; > > This is not symmetric with ls2x_rtc_time_to_alarm_regs, how can it work? This is to avoid an "invalid alarm value" at boot time, which of course should not be a good solution. When the alarm value is read at boot time, "year" is not yet set to the proper value so the year is always set to 1900. How about just "tm->tm_year = -1", as the alarm is now only read when booting? > > > +} > > + > > +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, > > + struct ls2x_rtc_regs *regs) > > +{ > > + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); > > +} > > + > > +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) > > +{ > > + int ret; > > + struct ls2x_rtc_regs regs; > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > + > > + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); > > + if (ret < 0) > > + return ret; > > + > > + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); > > + if (ret < 0) > > + return ret; > > + > > I never got a reply to my question: > > " > I'm actually wondering why you read first TOY_READ1_REG then > TOY_READ0_REG. ls1x does the opposite and the ls1c datasheet I found > doesn't mention any latching happening. So unless latching is done on > TOY_READ1_REG, you could use regmap_bulk_read and simply avoid struct > ls2x_rtc_regs. > If there is no latching, you may need to read TOY_READ0_REG at least > twice. Because TOY_READ1_REG only contains the year, it is an issue only > on 31 of December and it will not be easy to reproduce. > " > The LS7A and Loongson-2K datasheets also do not mention any latching happening. Reading TOY_READ1_REG first is probably just a matter of habit. I tried using regmap_bulk_xxx() and it also reads and writes time properly. In the next version I will rewrite this part of the code. Example: #define LS2X_NUM_TIME_REGS 2 u32 rtc_data[LS2X_NUM_TIME_REGS]; struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); ret = regmap_bulk_read(priv->regmap, TOY_READ0_REG, rtc_data, LS2X_NUM_TIME_REGS); > > > + ls2x_rtc_regs_to_time(®s, tm); > > + return 0; > > +} > > + > > +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) > > +{ > > + int ret; > > + struct ls2x_rtc_regs regs; > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > + > > + ls2x_rtc_time_to_regs(tm, ®s); > > + > > + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); > > + if (ret < 0) > > + return ret; > > + > > + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); > > +} > > + > > +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > +{ > > + int ret; > > + struct ls2x_rtc_regs regs; > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > + > > + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); > > + if (ret < 0) > > + return ret; > > + > > + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); > > + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); > > + > > + return 0; > > +} > > + > > +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > > +{ > > + u32 val; > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > + > > + spin_lock(&priv->rtc_reglock); > > + val = readl(priv->acpi_base + PM1_EN_REG); > > + > > + /* Enalbe RTC alarm */ > Typo > > > + writel((enabled ? val | RTC_EN : val & ~RTC_EN), > > + priv->acpi_base + PM1_EN_REG); > > + spin_unlock(&priv->rtc_reglock); > > + > > + return 0; > > +} > > + > > +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > +{ > > + int ret; > > + struct ls2x_rtc_regs regs; > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > + > > + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); > > + > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); > > + if (ret < 0) > > + return ret; > > + > > + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); > > +} > > + > > +static const struct rtc_class_ops ls2x_rtc_ops = { > > + .read_time = ls2x_rtc_read_time, > > + .set_time = ls2x_rtc_set_time, > > + .read_alarm = ls2x_rtc_read_alarm, > > + .set_alarm = ls2x_rtc_set_alarm, > > + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, > > +}; > > + > > +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) > > +{ > > + u32 val; > > + int ret; > > + > > + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); > > + if (ret < 0) > > + return ret; > > + > > + return regmap_write(priv->regmap, RTC_CTRL_REG, > > + val | TOY_ENABLE | OSC_ENABLE); > > +} > > + > > +static int ls2x_rtc_probe(struct platform_device *pdev) > > +{ > > + int ret; > > + void __iomem *regs; > > + struct ls2x_rtc_priv *priv; > > + struct device *dev = &pdev->dev; > > + > > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > > + if (!priv) > > + return -ENOMEM; > > + > > + priv->irq = platform_get_irq(pdev, 0); > > + if (priv->irq < 0) > > + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); > > + > > + platform_set_drvdata(pdev, priv); > > + > > + regs = devm_platform_ioremap_resource(pdev, 0); > > + if (IS_ERR(regs)) > > + return dev_err_probe(dev, PTR_ERR(regs), > > + "devm_platform_ioremap_resource failed\n"); > > + > > + priv->regmap = devm_regmap_init_mmio(dev, regs, > > + &ls2x_rtc_regmap_config); > > + if (IS_ERR(priv->regmap)) > > + return dev_err_probe(dev, PTR_ERR(priv->regmap), > > + "devm_regmap_init_mmio failed\n"); > > + > > + priv->rtcdev = devm_rtc_allocate_device(dev); > > + if (IS_ERR(priv->rtcdev)) > > + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), > > + "devm_rtc_allocate_device failed\n"); > > + > > + /* Due to hardware erratum, all years multiple of 4 are considered > > + * leap year, so only years 2000 through 2099 are usable. > > + * > > + * Previous out-of-tree versions of this driver wrote tm_year directly > > + * into the year register, so epoch 2000 must be used to preserve > > + * semantics on shipped systems. > > + */ > > + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; > > + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; > > + priv->rtcdev->ops = &ls2x_rtc_ops; > > + priv->acpi_base = regs - PM_RTC_OFFSET; > > + spin_lock_init(&priv->rtc_reglock); > > + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); > > Why? If you don't clear UIE, on the Loongson-2k, the shutdown will turn into a reboot after setting up the wakealarm. > > > + > > +#ifdef CONFIG_ACPI > > + if (!acpi_disabled) > > + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, > > + ls2x_acpi_fix_handler, priv); > > +#endif > > + > > + ret = ls2x_enable_rtc(priv); > > + if (ret < 0) > > + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); > > This should not be done in probe but on the first set_time. This then > allows you to know whether the time has been set and is valid in > read_time. Please add the check. Actually I don't quite understand the point you are making, the function just enables the TOY counter, would there be any particular problem with calling it in the probe function? Thanks. Binbin > > > + > > + ret = devm_request_threaded_irq(dev, priv->irq, NULL, ls2x_rtc_isr, > > + IRQF_TRIGGER_RISING | IRQF_ONESHOT, > > + "ls2x-alarm", priv); > > + if (ret < 0) > > + return dev_err_probe(dev, ret, "Unable to request irq %d\n", > > + priv->irq); > > + > > + if (!device_can_wakeup(&pdev->dev)) > > + device_init_wakeup(dev, 1); > > + > > + return devm_rtc_register_device(priv->rtcdev); > > +} > > + > > +static const struct of_device_id ls2x_rtc_of_match[] = { > > + { .compatible = "loongson,ls2x-rtc" }, > > + { /* sentinel */ } > > +}; > > +MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match); > > + > > +static const struct acpi_device_id ls2x_rtc_acpi_match[] = { > > + { "LOON0001" }, /* Loongson LS7A */ > > + { } > > +}; > > +MODULE_DEVICE_TABLE(acpi, ls2x_rtc_acpi_match); > > + > > +static struct platform_driver ls2x_rtc_driver = { > > + .probe = ls2x_rtc_probe, > > + .driver = { > > + .name = "ls2x-rtc", > > + .of_match_table = ls2x_rtc_of_match, > > + .acpi_match_table = ls2x_rtc_acpi_match, > > + }, > > +}; > > + > > +module_platform_driver(ls2x_rtc_driver); > > + > > +MODULE_DESCRIPTION("Loongson LS2X RTC driver"); > > +MODULE_AUTHOR("WANG Xuerui <git@xen0n.name>"); > > +MODULE_AUTHOR("Huacai Chen <chenhuacai@kernel.org>"); > > +MODULE_AUTHOR("Binbin Zhou <zhoubinbin@loongson.cn>"); > > +MODULE_LICENSE("GPL"); > > -- > > 2.31.1 > > > > -- > Alexandre Belloni, co-owner and COO, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com >
On 01/02/2023 17:16:12+0800, Binbin Zhou wrote: > Hi Alexandre: > > Sorry for the late reply. > > On Tue, Jan 24, 2023 at 7:37 AM Alexandre Belloni > <alexandre.belloni@bootlin.com> wrote: > > > > Hello, > > > > > > On 09/01/2023 09:35:12+0800, Binbin Zhou wrote: > > > This RTC module is integrated into the Loongson-2K SoC and the LS7A > > > bridge chip. This version is almost entirely rewritten to make use of > > > current kernel API, and it supports both ACPI and DT. > > > > > > This driver is shared by MIPS-based Loongson-3A4000 system (use FDT) and > > > LoongArch-based Loongson-3A5000 system (use ACPI). > > > > > > > checkpatch.pl --strict complains, please fix the warnings and checks > > Got. > > > > > > > +#ifdef CONFIG_ACPI > > > +static u32 ls2x_acpi_fix_handler(void *id) > > > +{ > > > + int ret; > > > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > > > + > > > + spin_lock(&priv->rtc_reglock); > > > + > > > + /* Disable acpi rtc enabled */ > > > + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; > > > + writel(ret, priv->acpi_base + PM1_EN_REG); > > > + > > > + /* Clear acpi rtc interrupt Status */ > > > + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); > > > + > > > + spin_unlock(&priv->rtc_reglock); > > > + > > > + /* > > > + * The TOY_MATCH0_REG should be cleared 0 here, > > > + * otherwise the interrupt cannot be cleared. > > > + * Because the match condition is still satisfied > > > + */ > > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); > > > + if (ret < 0) > > > + return ret; > > > > How is this an ACPI related issue? I guess the same would happen on > > !ACPI. > > I just assumed that the function would only be called under CONFIG_ACPI. > > > > > + > > > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); > > > > This is not useful, at that time, userspace has had no chance to open > > the RTC device file as it is not created yet. > > > > > + return 0; > > > +} > > > +#endif > > > + > > > +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, > > > > Those static inline functions seem to be used only once, you should just > > put the code in the proper location. > > I will do it in the next version. > > > > > + struct rtc_time *tm) > > > +{ > > > + tm->tm_year = regs->reg1; > > > + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); > > > + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); > > > + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); > > > + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); > > > + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; > > > +} > > > + > > > +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, > > > + struct ls2x_rtc_regs *regs) > > > +{ > > > + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); > > > + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); > > > + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); > > > + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); > > > + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); > > > + regs->reg1 = tm->tm_year; > > > +} > > > + > > > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > > > + struct rtc_time *tm) > > > +{ > > > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > > > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > > > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > > > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > > > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > > > + /* > > > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > > > + * years at most. Therefore, The RTC alarm years can be set from 1900 > > > + * to 1963. This causes the initialization of alarm fail during call > > > + * __rtc_read_alarm. > > > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > > > + * offset, the RTC alarm clock can be set from 1964 to 2027. > > > + */ > > > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; > > > > This is not symmetric with ls2x_rtc_time_to_alarm_regs, how can it work? > > This is to avoid an "invalid alarm value" at boot time, which of > course should not be a good solution. > When the alarm value is read at boot time, "year" is not yet set to > the proper value so the year is always set to 1900. Why isn't it set at boot time? Isn't the register persisting after a reboot? Setting a bogus alarm is not a solution. > > How about just "tm->tm_year = -1", as the alarm is now only read when booting? > > > > > > +} > > > + > > > +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, > > > + struct ls2x_rtc_regs *regs) > > > +{ > > > + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); > > > +} > > > + > > > +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) > > > +{ > > > + int ret; > > > + struct ls2x_rtc_regs regs; > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > + > > > + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); > > > + if (ret < 0) > > > + return ret; > > > + > > > + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); > > > + if (ret < 0) > > > + return ret; > > > + > > > > I never got a reply to my question: > > > > " > > I'm actually wondering why you read first TOY_READ1_REG then > > TOY_READ0_REG. ls1x does the opposite and the ls1c datasheet I found > > doesn't mention any latching happening. So unless latching is done on > > TOY_READ1_REG, you could use regmap_bulk_read and simply avoid struct > > ls2x_rtc_regs. > > If there is no latching, you may need to read TOY_READ0_REG at least > > twice. Because TOY_READ1_REG only contains the year, it is an issue only > > on 31 of December and it will not be easy to reproduce. > > " > > > > The LS7A and Loongson-2K datasheets also do not mention any latching > happening. Reading TOY_READ1_REG first is probably just a matter of > habit. > I tried using regmap_bulk_xxx() and it also reads and writes time > properly. In the next version I will rewrite this part of the code. > > Example: > > #define LS2X_NUM_TIME_REGS 2 > > u32 rtc_data[LS2X_NUM_TIME_REGS]; > struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > ret = regmap_bulk_read(priv->regmap, TOY_READ0_REG, rtc_data, > LS2X_NUM_TIME_REGS); > Doing a bulk read doesn't guarantee the atomicity of the operation. You really must check whether a register changed while reading the other one. > > > > > > + ls2x_rtc_regs_to_time(®s, tm); > > > + return 0; > > > +} > > > + > > > +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) > > > +{ > > > + int ret; > > > + struct ls2x_rtc_regs regs; > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > + > > > + ls2x_rtc_time_to_regs(tm, ®s); > > > + > > > + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); > > > + if (ret < 0) > > > + return ret; > > > + > > > + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); > > > +} > > > + > > > +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > > +{ > > > + int ret; > > > + struct ls2x_rtc_regs regs; > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > + > > > + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); > > > + if (ret < 0) > > > + return ret; > > > + > > > + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); > > > + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); > > > + > > > + return 0; > > > +} > > > + > > > +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > > > +{ > > > + u32 val; > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > + > > > + spin_lock(&priv->rtc_reglock); > > > + val = readl(priv->acpi_base + PM1_EN_REG); > > > + > > > + /* Enalbe RTC alarm */ > > Typo > > > > > + writel((enabled ? val | RTC_EN : val & ~RTC_EN), > > > + priv->acpi_base + PM1_EN_REG); > > > + spin_unlock(&priv->rtc_reglock); > > > + > > > + return 0; > > > +} > > > + > > > +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > > +{ > > > + int ret; > > > + struct ls2x_rtc_regs regs; > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > + > > > + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); > > > + > > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); > > > + if (ret < 0) > > > + return ret; > > > + > > > + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); > > > +} > > > + > > > +static const struct rtc_class_ops ls2x_rtc_ops = { > > > + .read_time = ls2x_rtc_read_time, > > > + .set_time = ls2x_rtc_set_time, > > > + .read_alarm = ls2x_rtc_read_alarm, > > > + .set_alarm = ls2x_rtc_set_alarm, > > > + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, > > > +}; > > > + > > > +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) > > > +{ > > > + u32 val; > > > + int ret; > > > + > > > + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); > > > + if (ret < 0) > > > + return ret; > > > + > > > + return regmap_write(priv->regmap, RTC_CTRL_REG, > > > + val | TOY_ENABLE | OSC_ENABLE); > > > +} > > > + > > > +static int ls2x_rtc_probe(struct platform_device *pdev) > > > +{ > > > + int ret; > > > + void __iomem *regs; > > > + struct ls2x_rtc_priv *priv; > > > + struct device *dev = &pdev->dev; > > > + > > > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > > > + if (!priv) > > > + return -ENOMEM; > > > + > > > + priv->irq = platform_get_irq(pdev, 0); > > > + if (priv->irq < 0) > > > + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); > > > + > > > + platform_set_drvdata(pdev, priv); > > > + > > > + regs = devm_platform_ioremap_resource(pdev, 0); > > > + if (IS_ERR(regs)) > > > + return dev_err_probe(dev, PTR_ERR(regs), > > > + "devm_platform_ioremap_resource failed\n"); > > > + > > > + priv->regmap = devm_regmap_init_mmio(dev, regs, > > > + &ls2x_rtc_regmap_config); > > > + if (IS_ERR(priv->regmap)) > > > + return dev_err_probe(dev, PTR_ERR(priv->regmap), > > > + "devm_regmap_init_mmio failed\n"); > > > + > > > + priv->rtcdev = devm_rtc_allocate_device(dev); > > > + if (IS_ERR(priv->rtcdev)) > > > + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), > > > + "devm_rtc_allocate_device failed\n"); > > > + > > > + /* Due to hardware erratum, all years multiple of 4 are considered > > > + * leap year, so only years 2000 through 2099 are usable. > > > + * > > > + * Previous out-of-tree versions of this driver wrote tm_year directly > > > + * into the year register, so epoch 2000 must be used to preserve > > > + * semantics on shipped systems. > > > + */ > > > + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; > > > + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; > > > + priv->rtcdev->ops = &ls2x_rtc_ops; > > > + priv->acpi_base = regs - PM_RTC_OFFSET; > > > + spin_lock_init(&priv->rtc_reglock); > > > + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); > > > > Why? > > If you don't clear UIE, on the Loongson-2k, the shutdown will turn > into a reboot after setting up the wakealarm. > Why? I don't get how UIE can have this effect. > > > > > + > > > +#ifdef CONFIG_ACPI > > > + if (!acpi_disabled) > > > + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, > > > + ls2x_acpi_fix_handler, priv); > > > +#endif > > > + > > > + ret = ls2x_enable_rtc(priv); > > > + if (ret < 0) > > > + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); > > > > This should not be done in probe but on the first set_time. This then > > allows you to know whether the time has been set and is valid in > > read_time. Please add the check. > > Actually I don't quite understand the point you are making, the > function just enables the TOY counter, would there be any particular > problem with calling it in the probe function? > Yes, you are losing an important bit of information which is that if TOY_ENABLE is not set, then you know the time has not been set. Else, you allow reading an known invalid time.
On Wed, Feb 15, 2023 at 7:13 AM Alexandre Belloni <alexandre.belloni@bootlin.com> wrote: > > On 01/02/2023 17:16:12+0800, Binbin Zhou wrote: > > Hi Alexandre: > > > > Sorry for the late reply. > > > > On Tue, Jan 24, 2023 at 7:37 AM Alexandre Belloni > > <alexandre.belloni@bootlin.com> wrote: > > > > > > Hello, > > > > > > > > > On 09/01/2023 09:35:12+0800, Binbin Zhou wrote: > > > > This RTC module is integrated into the Loongson-2K SoC and the LS7A > > > > bridge chip. This version is almost entirely rewritten to make use of > > > > current kernel API, and it supports both ACPI and DT. > > > > > > > > This driver is shared by MIPS-based Loongson-3A4000 system (use FDT) and > > > > LoongArch-based Loongson-3A5000 system (use ACPI). > > > > > > > > > > checkpatch.pl --strict complains, please fix the warnings and checks > > > > Got. > > > > > > > > > > +#ifdef CONFIG_ACPI > > > > +static u32 ls2x_acpi_fix_handler(void *id) > > > > +{ > > > > + int ret; > > > > + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; > > > > + > > > > + spin_lock(&priv->rtc_reglock); > > > > + > > > > + /* Disable acpi rtc enabled */ > > > > + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; > > > > + writel(ret, priv->acpi_base + PM1_EN_REG); > > > > + > > > > + /* Clear acpi rtc interrupt Status */ > > > > + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); > > > > + > > > > + spin_unlock(&priv->rtc_reglock); > > > > + > > > > + /* > > > > + * The TOY_MATCH0_REG should be cleared 0 here, > > > > + * otherwise the interrupt cannot be cleared. > > > > + * Because the match condition is still satisfied > > > > + */ > > > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); > > > > + if (ret < 0) > > > > + return ret; > > > > > > How is this an ACPI related issue? I guess the same would happen on > > > !ACPI. > > > > I just assumed that the function would only be called under CONFIG_ACPI. > > > > > > > + > > > > + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); > > > > > > This is not useful, at that time, userspace has had no chance to open > > > the RTC device file as it is not created yet. > > > > > > > + return 0; > > > > +} > > > > +#endif > > > > + > > > > +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, > > > > > > Those static inline functions seem to be used only once, you should just > > > put the code in the proper location. > > > > I will do it in the next version. > > > > > > > + struct rtc_time *tm) > > > > +{ > > > > + tm->tm_year = regs->reg1; > > > > + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); > > > > + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); > > > > + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); > > > > + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); > > > > + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; > > > > +} > > > > + > > > > +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, > > > > + struct ls2x_rtc_regs *regs) > > > > +{ > > > > + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); > > > > + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); > > > > + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); > > > > + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); > > > > + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); > > > > + regs->reg1 = tm->tm_year; > > > > +} > > > > + > > > > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > > > > + struct rtc_time *tm) > > > > +{ > > > > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > > > > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > > > > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > > > > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > > > > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > > > > + /* > > > > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > > > > + * years at most. Therefore, The RTC alarm years can be set from 1900 > > > > + * to 1963. This causes the initialization of alarm fail during call > > > > + * __rtc_read_alarm. > > > > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > > > > + * offset, the RTC alarm clock can be set from 1964 to 2027. > > > > + */ > > > > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; > > > > > > This is not symmetric with ls2x_rtc_time_to_alarm_regs, how can it work? > > > > This is to avoid an "invalid alarm value" at boot time, which of > > course should not be a good solution. > > When the alarm value is read at boot time, "year" is not yet set to > > the proper value so the year is always set to 1900. > > Why isn't it set at boot time? Isn't the register persisting after a > reboot? > Setting a bogus alarm is not a solution. > Hi, Alexandre: Sorry, I seem to have misled the issue. This is a hardware bug, as we know from the datasheet, the year field in the TOY_MATCH register has only 6 bits (bit[31:26]), so the maximum value is 63. For example, 2023 can only be read here as 1959, resulting in an invalid alarm. The current workaround: after reading the year field in ls2x_rtc_read_alarm(), manually add 64 or a multiple of 64 (equivalent to completing the high bits), which also ensures that the reading and writing is consistent. > > > > How about just "tm->tm_year = -1", as the alarm is now only read when booting? > > > > > > > > > +} > > > > + > > > > +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, > > > > + struct ls2x_rtc_regs *regs) > > > > +{ > > > > + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); > > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); > > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); > > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); > > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); > > > > + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); > > > > +} > > > > + > > > > +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) > > > > +{ > > > > + int ret; > > > > + struct ls2x_rtc_regs regs; > > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > + > > > > + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > > > I never got a reply to my question: > > > > > > " > > > I'm actually wondering why you read first TOY_READ1_REG then > > > TOY_READ0_REG. ls1x does the opposite and the ls1c datasheet I found > > > doesn't mention any latching happening. So unless latching is done on > > > TOY_READ1_REG, you could use regmap_bulk_read and simply avoid struct > > > ls2x_rtc_regs. > > > If there is no latching, you may need to read TOY_READ0_REG at least > > > twice. Because TOY_READ1_REG only contains the year, it is an issue only > > > on 31 of December and it will not be easy to reproduce. > > > " > > > > > > > The LS7A and Loongson-2K datasheets also do not mention any latching > > happening. Reading TOY_READ1_REG first is probably just a matter of > > habit. > > I tried using regmap_bulk_xxx() and it also reads and writes time > > properly. In the next version I will rewrite this part of the code. > > > > Example: > > > > #define LS2X_NUM_TIME_REGS 2 > > > > u32 rtc_data[LS2X_NUM_TIME_REGS]; > > struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > ret = regmap_bulk_read(priv->regmap, TOY_READ0_REG, rtc_data, > > LS2X_NUM_TIME_REGS); > > > > Doing a bulk read doesn't guarantee the atomicity of the operation. You > really must check whether a register changed while reading the other > one. > How about protecting with mutex? > > > > > > > > > + ls2x_rtc_regs_to_time(®s, tm); > > > > + return 0; > > > > +} > > > > + > > > > +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) > > > > +{ > > > > + int ret; > > > > + struct ls2x_rtc_regs regs; > > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > + > > > > + ls2x_rtc_time_to_regs(tm, ®s); > > > > + > > > > + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); > > > > +} > > > > + > > > > +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > > > +{ > > > > + int ret; > > > > + struct ls2x_rtc_regs regs; > > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > + > > > > + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); > > > > + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); > > > > + > > > > + return 0; > > > > +} > > > > + > > > > +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) > > > > +{ > > > > + u32 val; > > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > + > > > > + spin_lock(&priv->rtc_reglock); > > > > + val = readl(priv->acpi_base + PM1_EN_REG); > > > > + > > > > + /* Enalbe RTC alarm */ > > > Typo > > > > > > > + writel((enabled ? val | RTC_EN : val & ~RTC_EN), > > > > + priv->acpi_base + PM1_EN_REG); > > > > + spin_unlock(&priv->rtc_reglock); > > > > + > > > > + return 0; > > > > +} > > > > + > > > > +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) > > > > +{ > > > > + int ret; > > > > + struct ls2x_rtc_regs regs; > > > > + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > + > > > > + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); > > > > + > > > > + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); > > > > +} > > > > + > > > > +static const struct rtc_class_ops ls2x_rtc_ops = { > > > > + .read_time = ls2x_rtc_read_time, > > > > + .set_time = ls2x_rtc_set_time, > > > > + .read_alarm = ls2x_rtc_read_alarm, > > > > + .set_alarm = ls2x_rtc_set_alarm, > > > > + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, > > > > +}; > > > > + > > > > +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) > > > > +{ > > > > + u32 val; > > > > + int ret; > > > > + > > > > + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); > > > > + if (ret < 0) > > > > + return ret; > > > > + > > > > + return regmap_write(priv->regmap, RTC_CTRL_REG, > > > > + val | TOY_ENABLE | OSC_ENABLE); > > > > +} > > > > + > > > > +static int ls2x_rtc_probe(struct platform_device *pdev) > > > > +{ > > > > + int ret; > > > > + void __iomem *regs; > > > > + struct ls2x_rtc_priv *priv; > > > > + struct device *dev = &pdev->dev; > > > > + > > > > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > > > > + if (!priv) > > > > + return -ENOMEM; > > > > + > > > > + priv->irq = platform_get_irq(pdev, 0); > > > > + if (priv->irq < 0) > > > > + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); > > > > + > > > > + platform_set_drvdata(pdev, priv); > > > > + > > > > + regs = devm_platform_ioremap_resource(pdev, 0); > > > > + if (IS_ERR(regs)) > > > > + return dev_err_probe(dev, PTR_ERR(regs), > > > > + "devm_platform_ioremap_resource failed\n"); > > > > + > > > > + priv->regmap = devm_regmap_init_mmio(dev, regs, > > > > + &ls2x_rtc_regmap_config); > > > > + if (IS_ERR(priv->regmap)) > > > > + return dev_err_probe(dev, PTR_ERR(priv->regmap), > > > > + "devm_regmap_init_mmio failed\n"); > > > > + > > > > + priv->rtcdev = devm_rtc_allocate_device(dev); > > > > + if (IS_ERR(priv->rtcdev)) > > > > + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), > > > > + "devm_rtc_allocate_device failed\n"); > > > > + > > > > + /* Due to hardware erratum, all years multiple of 4 are considered > > > > + * leap year, so only years 2000 through 2099 are usable. > > > > + * > > > > + * Previous out-of-tree versions of this driver wrote tm_year directly > > > > + * into the year register, so epoch 2000 must be used to preserve > > > > + * semantics on shipped systems. > > > > + */ > > > > + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; > > > > + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; > > > > + priv->rtcdev->ops = &ls2x_rtc_ops; > > > > + priv->acpi_base = regs - PM_RTC_OFFSET; > > > > + spin_lock_init(&priv->rtc_reglock); > > > > + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); > > > > > > Why? > > > > If you don't clear UIE, on the Loongson-2k, the shutdown will turn > > into a reboot after setting up the wakealarm. > > > > Why? I don't get how UIE can have this effect. > In fact, we need to clear the RTC wakeup interrupt manually. I will fix this in the next release and remove clear_bit(). > > > > > > > + > > > > +#ifdef CONFIG_ACPI > > > > + if (!acpi_disabled) > > > > + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, > > > > + ls2x_acpi_fix_handler, priv); > > > > +#endif > > > > + > > > > + ret = ls2x_enable_rtc(priv); > > > > + if (ret < 0) > > > > + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); > > > > > > This should not be done in probe but on the first set_time. This then > > > allows you to know whether the time has been set and is valid in > > > read_time. Please add the check. > > > > Actually I don't quite understand the point you are making, the > > function just enables the TOY counter, would there be any particular > > problem with calling it in the probe function? > > > > Yes, you are losing an important bit of information which is that if > TOY_ENABLE is not set, then you know the time has not been set. Else, > you allow reading an known invalid time. > I will enable the RTC in set_time() and check in read_time() that it has been enabled Thanks. Binbin > > -- > Alexandre Belloni, co-owner and COO, Bootlin > Embedded Linux and Kernel engineering > https://bootlin.com
On 27/02/2023 10:26:09+0800, Binbin Zhou wrote: > > > > > +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, > > > > > + struct rtc_time *tm) > > > > > +{ > > > > > + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); > > > > > + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); > > > > > + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); > > > > > + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); > > > > > + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; > > > > > + /* > > > > > + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 > > > > > + * years at most. Therefore, The RTC alarm years can be set from 1900 > > > > > + * to 1963. This causes the initialization of alarm fail during call > > > > > + * __rtc_read_alarm. > > > > > + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the > > > > > + * offset, the RTC alarm clock can be set from 1964 to 2027. > > > > > + */ > > > > > + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; > > > > > > > > This is not symmetric with ls2x_rtc_time_to_alarm_regs, how can it work? > > > > > > This is to avoid an "invalid alarm value" at boot time, which of > > > course should not be a good solution. > > > When the alarm value is read at boot time, "year" is not yet set to > > > the proper value so the year is always set to 1900. > > > > Why isn't it set at boot time? Isn't the register persisting after a > > reboot? > > Setting a bogus alarm is not a solution. > > > > Hi, Alexandre: > > Sorry, I seem to have misled the issue. > This is a hardware bug, as we know from the datasheet, the year field > in the TOY_MATCH register has only 6 bits (bit[31:26]), so the maximum > value is 63. For example, 2023 can only be read here as 1959, > resulting in an invalid alarm. > The current workaround: after reading the year field in > ls2x_rtc_read_alarm(), manually add 64 or a multiple of 64 (equivalent > to completing the high bits), which also ensures that the reading and > writing is consistent. My first complain was that this is not symmetric with ls2x_rtc_time_to_alarm_regs. If you are adding 64 when reading the alarm, you need to remove 64 when setting the alarm. Now I get that FIELD_PREP will drop the overflowing bits. Instead of having support for the 1964 to 2027 range, you should probably aim for 2000 to 2064. Also, this makes me realize that you are not setting the year properly, the datasheet I have says that the supported year goes from 00 to 99. This is also what you set in .probe. Removing 100 from tm_year when setting and adding it back when reading would fix all of that. > > > The LS7A and Loongson-2K datasheets also do not mention any latching > > > happening. Reading TOY_READ1_REG first is probably just a matter of > > > habit. > > > I tried using regmap_bulk_xxx() and it also reads and writes time > > > properly. In the next version I will rewrite this part of the code. > > > > > > Example: > > > > > > #define LS2X_NUM_TIME_REGS 2 > > > > > > u32 rtc_data[LS2X_NUM_TIME_REGS]; > > > struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); > > > > > > ret = regmap_bulk_read(priv->regmap, TOY_READ0_REG, rtc_data, > > > LS2X_NUM_TIME_REGS); > > > > > > > Doing a bulk read doesn't guarantee the atomicity of the operation. You > > really must check whether a register changed while reading the other > > one. > > > > How about protecting with mutex? > No, this would fix multiple processes accessing a variable, here what you have are two unsynchronized hardware registers.
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index bb63edb507da..f8586aa00fce 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -1735,6 +1735,17 @@ config RTC_DRV_LPC32XX This driver can also be built as a module. If so, the module will be called rtc-lpc32xx. +config RTC_DRV_LS2X + tristate "Loongson LS2X RTC" + depends on MACH_LOONGSON64 || COMPILE_TEST + select REGMAP_MMIO + help + If you say yes here you get support for the RTC on the Loongson-2K + SoC and LS7A bridge, which first appeared on the Loongson-2H. + + This driver can also be built as a module. If so, the module + will be called rtc-ls2x. + config RTC_DRV_PM8XXX tristate "Qualcomm PMIC8XXX RTC" depends on MFD_PM8XXX || MFD_SPMI_PMIC || COMPILE_TEST diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index aab22bc63432..d5a467e9eec8 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -83,6 +83,7 @@ obj-$(CONFIG_RTC_DRV_LOONGSON1) += rtc-ls1x.o obj-$(CONFIG_RTC_DRV_LP8788) += rtc-lp8788.o obj-$(CONFIG_RTC_DRV_LPC24XX) += rtc-lpc24xx.o obj-$(CONFIG_RTC_DRV_LPC32XX) += rtc-lpc32xx.o +obj-$(CONFIG_RTC_DRV_LS2X) += rtc-ls2x.o obj-$(CONFIG_RTC_DRV_M41T80) += rtc-m41t80.o obj-$(CONFIG_RTC_DRV_M41T93) += rtc-m41t93.o obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o diff --git a/drivers/rtc/rtc-ls2x.c b/drivers/rtc/rtc-ls2x.c new file mode 100644 index 000000000000..06ef249a9485 --- /dev/null +++ b/drivers/rtc/rtc-ls2x.c @@ -0,0 +1,379 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Loongson-2K/LS7A RTC driver + * + * Based on the original out-of-tree Loongson-2H RTC driver for Linux 2.6.32, + * by Shaozong Liu <liushaozong@loongson.cn>. + * + * Maintained out-of-tree by Huacai Chen <chenhuacai@kernel.org>. + * Rewritten for mainline by WANG Xuerui <git@xen0n.name>. + * Binbin Zhou <zhoubinbin@loongson.cn> + */ + +#include <linux/bitfield.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/rtc.h> +#include <linux/acpi.h> + +/* Time Of Year(TOY) counters registers */ +#define TOY_TRIM_REG 0x20 /* Must be initialized to 0 */ +#define TOY_WRITE0_REG 0x24 /* TOY low 32-bit value (write-only) */ +#define TOY_WRITE1_REG 0x28 /* TOY high 32-bit value (write-only) */ +#define TOY_READ0_REG 0x2c /* TOY low 32-bit value (read-only) */ +#define TOY_READ1_REG 0x30 /* TOY high 32-bit value (read-only) */ +#define TOY_MATCH0_REG 0x34 /* TOY timing interrupt 0 */ +#define TOY_MATCH1_REG 0x38 /* TOY timing interrupt 1 */ +#define TOY_MATCH2_REG 0x3c /* TOY timing interrupt 2 */ + +/* RTC counters registers */ +#define RTC_CTRL_REG 0x40 /* TOY and RTC control register */ +#define RTC_TRIM_REG 0x60 /* Must be initialized to 0 */ +#define RTC_WRITE0_REG 0x64 /* RTC counters value (write-only) */ +#define RTC_READ0_REG 0x68 /* RTC counters value (read-only) */ +#define RTC_MATCH0_REG 0x6c /* RTC timing interrupt 0 */ +#define RTC_MATCH1_REG 0x70 /* RTC timing interrupt 1 */ +#define RTC_MATCH2_REG 0x74 /* RTC timing interrupt 2 */ + +/* TOY_WRITE0_REG bitmask */ +#define TOY_MON GENMASK(31, 26) +#define TOY_DAY GENMASK(25, 21) +#define TOY_HOUR GENMASK(20, 16) +#define TOY_MIN GENMASK(15, 10) +#define TOY_SEC GENMASK(9, 4) +#define TOY_MSEC GENMASK(3, 0) + +/* TOY_MATCH0/1/2_REG bitmask */ +#define TOY_MATCH_YEAR GENMASK(31, 26) +#define TOY_MATCH_MON GENMASK(25, 22) +#define TOY_MATCH_DAY GENMASK(21, 17) +#define TOY_MATCH_HOUR GENMASK(16, 12) +#define TOY_MATCH_MIN GENMASK(11, 6) +#define TOY_MATCH_SEC GENMASK(5, 0) + +/* RTC_CTRL_REG bitmask */ +#define RTC_ENABLE BIT(13) /* 1: RTC counters enable */ +#define TOY_ENABLE BIT(11) /* 1: TOY counters enable */ +#define OSC_ENABLE BIT(8) /* 1: 32.768k crystal enable */ + +/* Offset of PM domain from RTC domain */ +#define PM_RTC_OFFSET 0x100 + +/* PM domain registers */ +#define PM1_STS_REG 0x0c /* Power management 1 status register */ +#define RTC_STS BIT(10) /* RTC status */ +#define PM1_EN_REG 0x10 /* Power management 1 enable register */ +#define RTC_EN BIT(10) /* RTC event enable */ + +struct ls2x_rtc_priv { + spinlock_t rtc_reglock; + int irq; + struct rtc_device *rtcdev; + struct regmap *regmap; + void __iomem *acpi_base; +}; + +static const struct regmap_config ls2x_rtc_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +struct ls2x_rtc_regs { + u32 reg0; + u32 reg1; +}; + +/* IRQ Handlers */ +static irqreturn_t ls2x_rtc_isr(int irq, void *id) +{ + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; + + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); + return IRQ_HANDLED; +} + +#ifdef CONFIG_ACPI +static u32 ls2x_acpi_fix_handler(void *id) +{ + int ret; + struct ls2x_rtc_priv *priv = (struct ls2x_rtc_priv *)id; + + spin_lock(&priv->rtc_reglock); + + /* Disable acpi rtc enabled */ + ret = readl(priv->acpi_base + PM1_EN_REG) & ~RTC_EN; + writel(ret, priv->acpi_base + PM1_EN_REG); + + /* Clear acpi rtc interrupt Status */ + writel(RTC_STS, priv->acpi_base + PM1_STS_REG); + + spin_unlock(&priv->rtc_reglock); + + /* + * The TOY_MATCH0_REG should be cleared 0 here, + * otherwise the interrupt cannot be cleared. + * Because the match condition is still satisfied + */ + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, 0); + if (ret < 0) + return ret; + + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); + return 0; +} +#endif + +static inline void ls2x_rtc_regs_to_time(struct ls2x_rtc_regs *regs, + struct rtc_time *tm) +{ + tm->tm_year = regs->reg1; + tm->tm_sec = FIELD_GET(TOY_SEC, regs->reg0); + tm->tm_min = FIELD_GET(TOY_MIN, regs->reg0); + tm->tm_hour = FIELD_GET(TOY_HOUR, regs->reg0); + tm->tm_mday = FIELD_GET(TOY_DAY, regs->reg0); + tm->tm_mon = FIELD_GET(TOY_MON, regs->reg0) - 1; +} + +static inline void ls2x_rtc_time_to_regs(struct rtc_time *tm, + struct ls2x_rtc_regs *regs) +{ + regs->reg0 = FIELD_PREP(TOY_SEC, tm->tm_sec); + regs->reg0 |= FIELD_PREP(TOY_MIN, tm->tm_min); + regs->reg0 |= FIELD_PREP(TOY_HOUR, tm->tm_hour); + regs->reg0 |= FIELD_PREP(TOY_DAY, tm->tm_mday); + regs->reg0 |= FIELD_PREP(TOY_MON, tm->tm_mon + 1); + regs->reg1 = tm->tm_year; +} + +static inline void ls2x_rtc_alarm_regs_to_time(struct ls2x_rtc_regs *regs, + struct rtc_time *tm) +{ + tm->tm_sec = FIELD_GET(TOY_MATCH_SEC, regs->reg0); + tm->tm_min = FIELD_GET(TOY_MATCH_MIN, regs->reg0); + tm->tm_hour = FIELD_GET(TOY_MATCH_HOUR, regs->reg0); + tm->tm_mday = FIELD_GET(TOY_MATCH_DAY, regs->reg0); + tm->tm_mon = FIELD_GET(TOY_MATCH_MON, regs->reg0) - 1; + /* + * The rtc SYS_TOYMATCH0/YEAR bit field is only 6 bits, so it means 63 + * years at most. Therefore, The RTC alarm years can be set from 1900 + * to 1963. This causes the initialization of alarm fail during call + * __rtc_read_alarm. + * We add 64 years offset to ls2x_rtc_read_alarm. After adding the + * offset, the RTC alarm clock can be set from 1964 to 2027. + */ + tm->tm_year = FIELD_GET(TOY_MATCH_YEAR, regs->reg0) + 64; +} + +static inline void ls2x_rtc_time_to_alarm_regs(struct rtc_time *tm, + struct ls2x_rtc_regs *regs) +{ + regs->reg0 = FIELD_PREP(TOY_MATCH_SEC, tm->tm_sec); + regs->reg0 |= FIELD_PREP(TOY_MATCH_MIN, tm->tm_min); + regs->reg0 |= FIELD_PREP(TOY_MATCH_HOUR, tm->tm_hour); + regs->reg0 |= FIELD_PREP(TOY_MATCH_DAY, tm->tm_mday); + regs->reg0 |= FIELD_PREP(TOY_MATCH_MON, tm->tm_mon + 1); + regs->reg0 |= FIELD_PREP(TOY_MATCH_YEAR, tm->tm_year); +} + +static int ls2x_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + int ret; + struct ls2x_rtc_regs regs; + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); + + ret = regmap_read(priv->regmap, TOY_READ1_REG, ®s.reg1); + if (ret < 0) + return ret; + + ret = regmap_read(priv->regmap, TOY_READ0_REG, ®s.reg0); + if (ret < 0) + return ret; + + ls2x_rtc_regs_to_time(®s, tm); + return 0; +} + +static int ls2x_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + int ret; + struct ls2x_rtc_regs regs; + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); + + ls2x_rtc_time_to_regs(tm, ®s); + + ret = regmap_write(priv->regmap, TOY_WRITE0_REG, regs.reg0); + if (ret < 0) + return ret; + + return regmap_write(priv->regmap, TOY_WRITE1_REG, regs.reg1); +} + +static int ls2x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + int ret; + struct ls2x_rtc_regs regs; + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); + + ret = regmap_read(priv->regmap, TOY_MATCH0_REG, ®s.reg0); + if (ret < 0) + return ret; + + ls2x_rtc_alarm_regs_to_time(®s, &alrm->time); + alrm->enabled = !!(readl(priv->acpi_base + PM1_EN_REG) & RTC_EN); + + return 0; +} + +static int ls2x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + u32 val; + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); + + spin_lock(&priv->rtc_reglock); + val = readl(priv->acpi_base + PM1_EN_REG); + + /* Enalbe RTC alarm */ + writel((enabled ? val | RTC_EN : val & ~RTC_EN), + priv->acpi_base + PM1_EN_REG); + spin_unlock(&priv->rtc_reglock); + + return 0; +} + +static int ls2x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + int ret; + struct ls2x_rtc_regs regs; + struct ls2x_rtc_priv *priv = dev_get_drvdata(dev); + + ls2x_rtc_time_to_alarm_regs(&alrm->time, ®s); + + ret = regmap_write(priv->regmap, TOY_MATCH0_REG, regs.reg0); + if (ret < 0) + return ret; + + return ls2x_rtc_alarm_irq_enable(dev, alrm->enabled); +} + +static const struct rtc_class_ops ls2x_rtc_ops = { + .read_time = ls2x_rtc_read_time, + .set_time = ls2x_rtc_set_time, + .read_alarm = ls2x_rtc_read_alarm, + .set_alarm = ls2x_rtc_set_alarm, + .alarm_irq_enable = ls2x_rtc_alarm_irq_enable, +}; + +static int ls2x_enable_rtc(struct ls2x_rtc_priv *priv) +{ + u32 val; + int ret; + + ret = regmap_read(priv->regmap, RTC_CTRL_REG, &val); + if (ret < 0) + return ret; + + return regmap_write(priv->regmap, RTC_CTRL_REG, + val | TOY_ENABLE | OSC_ENABLE); +} + +static int ls2x_rtc_probe(struct platform_device *pdev) +{ + int ret; + void __iomem *regs; + struct ls2x_rtc_priv *priv; + struct device *dev = &pdev->dev; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->irq = platform_get_irq(pdev, 0); + if (priv->irq < 0) + return dev_err_probe(dev, priv->irq, "platform_get_irq failed\n"); + + platform_set_drvdata(pdev, priv); + + regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(regs)) + return dev_err_probe(dev, PTR_ERR(regs), + "devm_platform_ioremap_resource failed\n"); + + priv->regmap = devm_regmap_init_mmio(dev, regs, + &ls2x_rtc_regmap_config); + if (IS_ERR(priv->regmap)) + return dev_err_probe(dev, PTR_ERR(priv->regmap), + "devm_regmap_init_mmio failed\n"); + + priv->rtcdev = devm_rtc_allocate_device(dev); + if (IS_ERR(priv->rtcdev)) + return dev_err_probe(dev, PTR_ERR(priv->rtcdev), + "devm_rtc_allocate_device failed\n"); + + /* Due to hardware erratum, all years multiple of 4 are considered + * leap year, so only years 2000 through 2099 are usable. + * + * Previous out-of-tree versions of this driver wrote tm_year directly + * into the year register, so epoch 2000 must be used to preserve + * semantics on shipped systems. + */ + priv->rtcdev->range_min = RTC_TIMESTAMP_BEGIN_2000; + priv->rtcdev->range_max = RTC_TIMESTAMP_END_2099; + priv->rtcdev->ops = &ls2x_rtc_ops; + priv->acpi_base = regs - PM_RTC_OFFSET; + spin_lock_init(&priv->rtc_reglock); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, priv->rtcdev->features); + +#ifdef CONFIG_ACPI + if (!acpi_disabled) + acpi_install_fixed_event_handler(ACPI_EVENT_RTC, + ls2x_acpi_fix_handler, priv); +#endif + + ret = ls2x_enable_rtc(priv); + if (ret < 0) + return dev_err_probe(dev, ret, "ls2x_enable_rtc failed\n"); + + ret = devm_request_threaded_irq(dev, priv->irq, NULL, ls2x_rtc_isr, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + "ls2x-alarm", priv); + if (ret < 0) + return dev_err_probe(dev, ret, "Unable to request irq %d\n", + priv->irq); + + if (!device_can_wakeup(&pdev->dev)) + device_init_wakeup(dev, 1); + + return devm_rtc_register_device(priv->rtcdev); +} + +static const struct of_device_id ls2x_rtc_of_match[] = { + { .compatible = "loongson,ls2x-rtc" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ls2x_rtc_of_match); + +static const struct acpi_device_id ls2x_rtc_acpi_match[] = { + { "LOON0001" }, /* Loongson LS7A */ + { } +}; +MODULE_DEVICE_TABLE(acpi, ls2x_rtc_acpi_match); + +static struct platform_driver ls2x_rtc_driver = { + .probe = ls2x_rtc_probe, + .driver = { + .name = "ls2x-rtc", + .of_match_table = ls2x_rtc_of_match, + .acpi_match_table = ls2x_rtc_acpi_match, + }, +}; + +module_platform_driver(ls2x_rtc_driver); + +MODULE_DESCRIPTION("Loongson LS2X RTC driver"); +MODULE_AUTHOR("WANG Xuerui <git@xen0n.name>"); +MODULE_AUTHOR("Huacai Chen <chenhuacai@kernel.org>"); +MODULE_AUTHOR("Binbin Zhou <zhoubinbin@loongson.cn>"); +MODULE_LICENSE("GPL");